Combined fire-alarm and gas-lighting apparatus



(No Model.) 3 Sheets-Sheet 1. G. D. BANCROPT.

Combined Fire Alarm and Gas Lighting Apparatus. No. 239,014. Patented March 22,1881.

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No Model.) 3 Sheets-Sheet 2.

G. D. BANO ROPT. CombinedfPire Alarm and Gas Lighting Apparatus. No. 239,014. Patented March 22,1881.

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, 3 Sheets-Sheet 3. G. D. BANGROFT. Combined Fire Alarm and Gas Lighting Apparatus.

Patented March 22,188].

(No Model.)

INVENTEIR I T N E 5 5 E 5 UNITED STATES PATENT ()FFICE.

GEORGE D. BANOROFT, OF BOSTON, MASSACHUSETTS.

COMBINED FIRE-ALARM AND GAS-LIGHTING APPARATUS.

SPECIFICATION forming part of Letters Patent No. 239,014, dated March'22, 1881.

Application filed December 8, 1880.

To all whom it may concern:

Be it known that I, GEORGE D. BANoEorT, of Boston, in the State of Massachusetts, have invented a new and useful lm in-ovement in Lighting Gas by Electricity in Combination with Fire-Alarms, of which the following is a specification.

The invention consists in placing a number of gas-burners in a fire-alarm circuit, and providing each burner and each fire-alarm box, respectively, with mechanism whereby the gas may be turned on and lighted or turned 0E and extinguished at all the burners simultaneously without operating or preventing the operation of the alarm mechanism, and whereby, on the other hand, an alarm may at any time be given from either alarm-box without interfering with the gaslighting mechanism.

It consists, further, in certain details which will hereinafter be particularly set forth.

In an application for a patent now pending I have described a group of gas-burners in a single electric circuit, each of which is furnished with an electro-magnet, an armature, and a thern'io-spring to operate the gas-cock, and a platinum wire in close proximity to the tip to light the gas by incandescence, all the electro-magnets and all the platinum wires being in the electric circuit, so that the gas may be simultaneously lighted or simultaneously extinguished at all the burners. I have now devised means for working a tirealarm apparatus in combination with the said gas-lighting apparatus with the employment of but very little additional wire, and I have made provision for giving an alarm at an alarm-box at the very instant at which the circuit is employed for lighting or extinguishing the gas.

The apparatus attached to each gas-burner will require but a brief description, being, in many respects, the same as that described in my Patent No. 205,032, and in no essential respect differing from that described in my said application.

In the drawings, Figure 1 is a front elevation of a burner with apparatus attached. Fig. 2 is a plan of the samewith the thermospring broken away. Fig. 3 is a side elevation with the thermo-spring broken at its heavier end. Fig. 4 is a sectional elevation of the same. Fig. 5 is a front elevation, and

(No model.)

an electro-magnct, bein a cylindrical box, of

iron, with a hollow core, (1, around which is wound a coarse wire, 0, as shown. The core 61 is threaded at the upper end to receive the gas-burner, and at the lower end to screw upon the gas-pipe.

E is the armature, hinged to the box, as shown, and when the magnet is demagnetized kept up by a spring, 8.

Gr is a thermo-spring, supported at one end by an arm extendingfrom the cylindrical box, and having its other end clamped in a block, f, sliding upon a rod, g, which, in turn, slides in a bracket upon the cylindrical box, and which, at its inner end, is attached to a crankpin, a, on the segmentarm 0. Proper nuts are used, as shown, to limit the motion of the block f upon the rod 9 and of the rod 9 through the said bracket. v

Behind the burner are shown two stiff heavy wires, w 20 which are united near the gas-tip by a platinum wire, 32. The wire 20 is connected with the coil 0, while the wire 10 goes to ground or to the line-wire. The armature E has holes to permit the passage of the wires w 20 and a large hole for the burner A. The armature has a projection, 1), against which one of the shoulders, 0 or c, ofthe segment-arm G catches. In the normal condition of the apparatus the shoulder c rests upon the projection I), and the cock is closed. The pressure of the thermo-spring is inward at ordinary temperatures and outward when heated by the flame of the gas. The end of the coil 0 not connected with wire 20 is connected with the main line.

The operation, accordingly, is as follows: A single impulse sent through the line causes the magnet D to attract its armature E, and thereby releases the shoulder c from projection I). The thermo-spring, being cold, presses the segment-arm O inward, opening the cock. In the meantime the platinum wirepis brought to a white heat and lights the gas. The current is now broken, and, the armature rising,

the shoulder c is caught upon projection b, and the cock thus kept open; but after a few minutes the thermo-spring becomes so heated that it exerts its force in the opposite direction, when a single impulse sent over the line vill shut off the gas.

I use a magneto-machine to generate the current, since a strong current is required to heat the platinum wire, and accordingly a heavy wire is used in the coil of the electromagnet.

I operate in a single circuit a large number of burners, each furnished with apparatus as above described, and I have devised means for combining therewith a fire-alarm system, as follows:

II is a fire-alarm box or casing.

I is an electro-magnet. J is its armature, upon a weighted arm, J, pivoted at cl to a stud projecting from the fire-alarm box. One end of the coil of the electro-magnet I is connected with the line-wire l, the other by a wire, 10 with plate P of the commutator P, of which the plate P is connected with linewire I. In the normal condition of the apparatus a connection is established between plates P and 13 by aimetallic bar, K, hinged as shown, and held down by springf.

L is a large pulley turning loosely upon shaft M, which has hearings in a frame within the fire-alarm box, as shown.

N is a ratchetwheel, and 0 a break-circuit wheel, fastened together by screws g g and turning with the shaft M. A pawl, (1 pivoted to pulley L, takes into the teeth of the ratchetwheel by force of spring m. Another pawl, R, pivoted to the frame at a, takes into the teeth of the ratchet-wheel N by force of the adjustable spring 0. This pawl R carries a pin, 6, which is embraced by a slot,j, in the arm J when the armature J is attracted to the electro-magnet I, whereby the {pawl R is locked upon a tooth ot' the ratchet-wheel N. A cord, 15, passes over the pulley L, having at one end a weight, W, working in a dash-pot, p, and at the other a bell-pull, T. Proper stops are used to limit the motion of the weight W in either direction, and, although not observed in the drawings, the proportions should be such that the pulley L will make an entire revolution while the weight W makes a full passage in either direction. A stop, 11 limits the upward motion of the arm J and armature J. A tooth, k, on the vibrating arm K follows the periphery of the circuit-breaker O,causing the circuit to be broken at the commutator 1? whenever the tooth strikes a projection on said periphery.

In the normal condition of the apparatus shown in the lire-alarm box H the circuit is closed, being in through line-wire l, to the coil of the electro-magnet I, thence by wire 10 to plate 1?, bar K, plate P and out through linewire I. The apparatus within the box, therefore, does not in its normal condition interfere with any use made of the line elsewhere.

As in other fire-alarms, many boxes may be placed upon the line; and it follows, from the description above, that the apparatus at one or more gas-burners may be placed in the same circuit, for although the electric gas-lighting system is operated upon an open circuit the circuit is never broken within the apparatus immediately connected with the burner, but only at the distant operating-station.

To ring an alarm at box H, above described, the operator pulls down the bell-pull T until the weightW strikes its upper stop. hen he lets go, the weight W causes the pulley L to make a revolution in the opposite direction, and thepawl d now takinginto ratchet-wheel N, carries with it wheels N and O, the latter, through the tooth k and arm K, breaking the circuit at P and ringing the distant bells in the ordinary manner.

The current employed for the fire-alarm system as just described has not sufficient strength to cause the electro-magnet I to attract its armature J. Since, however, as will hereinafter appear, a current of sufficient strength for this purpose is employed in working the gas-lighting apparatus, its eflect in the fire-alarm box may be here described. When by a strong current the armature J is attracted to its electro-magnet, the pin t is locked in the slot j, and the pawl R is thereby looked upon a tooth of the ratchet-wheel N. This does not prevent the revolution of the pulley L in one direction by a pull upon the bell-pull T but when the pulley L should return by force of the weightWit happens that the ratchet-wheel N is locked between the two pawls d and R, and all three wheels, L, N, and O, are held fast. When, however, the strong current no longer exists in the electromagnet, the weighted armature J rises and unlocks the pawl It, permitting the weightWV to operate the mechanism as before; and it follows that if an alarm is pulled at the lirealarm box H while the strong current is on the line for lighting the gas, the pull will be stored up in the apparatus to take effect immediately after the gas-lighting current is taken off the line. The manner in which the two systems are operated together, including the apparatus at the station from which the gas is lighted, is illustrated in the diagram at Fig. 7. The letters employed in the diagram refer to the parts to which they refer in the other figures; but, for convenience, numerals are employed to designate some of the wires.

A is a switch-board, B being a switch, and c 0 being two stops, connected, respectively, by wires 2 and 3, with binding-screws s and 8 The switch 13 has attached to it a piece of hard rubber, (1 against which a spring, d, presses when the switch is in contact with stop 0 The spring (1 is in metallic contact with binding-screw 8 which is grounded at G through wire 1. The spring (1 is of such width as to press against stop 0 when the switch 13 is removed therefrom. Binding-screw s is connected by wire at with the fire-alarm battery 13 from which wire 5 passes through the alarm bells B B to ground at G Binding-screw s is connected by wire 6 with a magneto-machine, M. which is grounded through wire 7 at G Wire 8 connects binding-screw s with ground at G after passing through the apparatus at all the fire-alarm boxes and the appa ratus at all the gas-burners, as above described. The switch B is electrically connected with binding-screw 8 In electric gas-lighting apparatus for streetlamps it has been found expedient to lay the line-wire under ground. Accordingly, I connect the fire-alarm boxes with such underground wire, which in the diagram is marked 8. The alarm-bells might also be connected with the same wire; but they would then strike whenever the strong current was sent over the line to light or extinguish the gas. I have therefore placed them upon a separate wire, (marked 5 in the diagram,) and this is not an underground wire but nevertheless I have effected a great saving of wire by my combination, since in all fire-alarm systems the number of alarm-boxes greatly exceeds the number of bells.

In the normal condition of the combined apparatus the switch B is in contact with stop 0 and the fire-alarm battery is in the circuit, which is as follows: From ground at G by wire 8 to burner 2, through that burner, includingits platinum wire 12 and coil 0, as before described, and out by wire 8 to box 2, and in that box through the commutator and the coil of the electro-magnet I, out by wire 8, and in like manner through burner l and box 1, wire 8, to binding-screw 8", switch 13, wire 3, binding-screw 3 wire 4, battery B and wire 5, through the alarm-bells B and B to ground at G An alarm may now be pulled, as before described, at either box 1 or box 2. It, now, the operator wishes to light or extinguish the gas, he shifts the switch B to stop 0 and generates a current by the magneto-machine. The hard rubber d is of such size and shape that the spring (1 strikes the stop 0 before the switch B breaks contact with that stop, thereby establishing a new ground for the alarm-bell circuit and preventing an alarm. The divided circuits-that is, the magnetocircuit through the alarm-boxes and burners, and the battery-circuit through the bellsare clearly shown'in the diagram. The operator having lighted or extinguished the gas, a spring, 61 pulls the switch B back to stop 0 and the normal condition of the circuits is established, when an alarm may be sounded from either of the boxes, or an alarm which has been stored up will be automatically sounded.

I claim-- 1. A group of gas-burners in an electric circuit in which the gas may be turned on or off and lighted or extinguished by mechanism under the control of a magneto-current, in combination with a fire-alarm box or boxes in the same circuit provided with mechanism which may be worked by a battery-currentto give an alarm, and a lock mechanism under the control of the magneto-current to store up an alarm when the circuit is occupied by the magneto-current, substantially as described.

2. A tire-alarm box provided with an ordinary circuit-breakin g mechanism adapted to be worked by a weak current to give an alarm, and provided, also, with a lock mechanism under the control of an electro-magnet in the alarm-circuit, which can be worked only by a stron current, substantially as described, for the purpose specified.

3. A series of gas-burners and a series of lirealarm boxes intermingled upon a single circuit, one series operated by a magneto-current and the other series by a battery-current, and the whole provided with a switch mechanism for bringing in either the magneto-current or the battery-current, in combination with an alarm-bell always in the battery-circuit, but short-circuited when the magneto-current is brought upon the main line.

4. A series of gas-burners and a series of lire-alarm boxes in a single circuit, each burner provided with suitable lighting mechanism controlled by a current of requisite strength, and each box with an ordinary circuit-breaking mechanism controlled by a current of lesser strength, in combination with batteries or electric machines for furnishing currents of electrieity of the two diii'erent strengths required, and switch mechanism for bringing one or the other of said currents upon the line, substantially as described.

GEORGE D. BANOROFT.

Witnesses W. W. SWAN, H. G. OLMSTED. 

